In recent years, in order to satisfy the diverse demands of mobile subscribers, not only higher downlink transmission data rate, but also higher uplink transmission data rate is required in 3G communication system. HSDPA (High Speed Downlink Packet Access) is packet-based data service, which enhances downlink transmission of mobile data. For the downlink channel (5 MHz bandwidth) in WCDMA system, the maximum transmission data rate supported by HSDPA can be up to 10 Mbps. The key technologies which HSDPA adopts are Adaptive Modulation and Coding (AMC) and Hybrid Automatic Repeat Request (HARQ). EUL (Enhanced Uplink) technology is proposed to improve uplink transmission data rate under the support of E-DCH (Enhanced-Dedicated Channel) technology. Nevertheless, in existing TDD specifications, there is no detailed definition for the physical layer architecture of E-DCH.
In addition, during traditional uplink data transmission, one issue is that the uplink channel is not allowed to be dynamically changed any more, once allocated. However, there would be considerable imbalance for traffic rate of uplink data, for instance, during communication process, when huge volume of data is needed to be transmitted, the capacity of the allocated channel can not satisfy the demands for transmitting such large amount of data, and when small volume of data transmission is needed, the spare channel resource will be wasted.
Therefore, a complete solution of method and apparatus for enhanced uplink data transmission is needed, which enables mobile terminal to conduct efficient uplink transmission.